Stone-crusher



P. BECHGAARD.

. STONE ORUSHER. mucmou FILED mac. n. 1920.

Pat ented 1m 13, 1921.

R Bec dmr PATENT OFFICE.

POUL BECHGAARD, OF DALBY, SWEDEN.

STONE-CRUSHER.

Application filed December 11, 1920.

T0 aZZ whom it may concern.

Be it known that 1, Poor BEOI-IGAARD, Z1 citizen of Sweden, and residing at Dalby, in the county of Malmohus, Kingdom of Sweden, have invented a new and useful improvement in Stone-Crushers, (for which I have filed an application in Sweden, March 26, 1919,) of which the following is a speciiication.

Most stone crushers consist of a fixed jaw, a jaw movable in relation thereto and two fixed side members, said parts forming together a chamber into which the stone materials to be crushed are fed. In such crushers a considerable drawback is to be found therein that the stone material, especially adjacent to the fixed aw, is amined in the angle between said jaw and the side members thus causing the material within the crushing chamber to be stopped up, thereby reducing the working capacity and making an often repeated wrenching oif of the jammed material by means of iron bars and the like necessary so as to keep the crusher normally and continuously in working order. Said drawback arises especially when using new crushing plates or working surfaces on the jaws and continues until the usually triangular ridges or corrugations thereof have been worn or flattened to a certain degree adjacent to the side members, but as these parts of the working surface are not exposed to such a heavy wearing as the central part thereof said latter part is normally worn out when the outer oarts adjacent to the side members are worn to such a degree that the drawback referred to has ceased. lVhen the central part has been worn out an exchange of crushing plate or generally of working surface of the same ,is however required so as to maintain the working capacity of the stone crusher and at such an exchange the outer parts of the working surface are renewed at the same time as the middle part and thus the drawback in question almost constantly is at hand.

According to the present invention the said drawback is removed in such a way that the working surface of the crushing plate from the beginning is given a form answering to the purpose required or in other words a form, which from the beginning corresponds to a certain degree of wear of the outer parts of the working surface, without the efficiency of the working surface be- Specification of Letters Patent.

Patented Dec. 13, 1921.

Serial No. 429,994.

ing diminished, which unavoidably is the case as a consequence of wear.

The invention is illustrated in the acco1n pany ing drawing, which shows a crushing aw in cross section positioned between two side members, which together with said jaw and another jaw coacting therewith shown in the drawing together form the crushing chamber referred to above.

The invention is especially intended to be put in practice with regard to fixed crushing jaws, because the same have no movement relatively to the side members and jamming therefore more frequently occurs in the arigle between these parts, but with the same advantage and without noticeable diminishing of the working capacity it may be used also with regard to the movable crushing jaw although in this case jamming because of the movement relatively to the side members less frequently occurs. If the working surface, e. the usually triangular ridges forming the same, is formed integral, with the body of the crushing jaw or if it is combined with an exchangeable crushing plate fixed to the body of the or eventually consists of separate and exchangeable bars or the like is of no consequence as the invention with the same advantage may be used in connection with all of these types of crushing jaws.

The characteristic featureof the invention consists simpl that the usually triangular ridges or waves formin the working surface of the crushing jaw at the middle thereof are higher, 7'. 8., extend farther from the base plane of the crushing plate, than the ridges or waves placed nearer to the outer edges of said plate, 2'. 6., the parts adjacent to the side members.

Referring to the drawing the reference 1 represents the movable crushing jaw and 1' the fixed crushing j aw, the working surface of each jaw consisting of seven parallel and triangular ridges, of which the three ridges 2 placed in the middle of the plate are of an equal height counted from the base plane of said plate. The two ridges 3 placed out side of the middle ones are somewhat lower and the outer ridges 4 are lower than the ridges 3. In itself this arrangement is satisfactory for obtaining a relatively good result, but if in addition thereto all of the ridges have a base surface of the same width the top angles of the ridges because of the gradually diminished height will be gradually increased toward the outer edges of the plate. The top angles of the ridges nearest to the side members 5 will be the largest ones and of course this fact improves the result aimed at, while thereby the angles between the side members and the sides of the outer ridges facing the same will be enlarged and jamming of the material in these angles will be prevented.

The cross sectional form of the working surface thus obtained insures an approximately uniform wearing all over the width of the surface and enables the crushing plate with full working capacity to be used during the longest possible time.

In the example shown in the drawing the three ridges placed in the middle are of an equal height, but this is not necessary and the middlemost one might be higher. Besides the number of ridges arranged on the same plate is of no consequence.

Having now described my invention and the manner in which the same is to be performed, I declare that what I claim is 1. Improvement in stone crushers having two crushing jaws-movable in relation to each other and side members which together with thejaws form a crushing chamber, said jaws being at the working surfaces provided with ridges of. such a height that the free space between the tops of the ridges on the opposite working surfaces of the coacting crushing jaws is less at the middle of the same and that said space is gradually increasing toward the outer parts adjacent to the side members.

2. Improvement in stone crushers having a. fixed crushing jaw, another jaw movable in relation thereto and two side members forming together with said jaws a crushing chamber, the fixed jaw being at the working surface provided with ridges of such a height that-the ridges placed in the middle of the Working surface are extending farther into the crushing chamber than the ridges placed nearer to the edges of said surface, the ridges lastmentioned gradually increasing in height toward the middle of the working surface.

3. Improvement in stone crushershaving two crushing jaws movable in relation to each other and side members which together with the jaws form a crushing chamber, said jaws being at the working surfaces provided with ridges triangular in cross section and of such a height that the free space between the tops of the ridges on the opposite working surfaces of the coacting crushing jaws is less at the middle of the same and gradually increasing toward the outer parts adj acent to the side members, the top angles of the ridges being gradually increased according to the gradual increasing distance be tween the jaws.

at. Improvement in stone crushers having a fixed crushing jaw, another jaw movable in relation thereto and two side members forming together with said jaws a crushing chamber, the fixed jaw 'at the working surface being provided with ridges triangular in cross section and of such a height that the ridges placed in the middle of the working surface are extending farther into the crushing chamber than the ridges placed nearer to the edges of said surface and nearer to the side members, the base surfaces of all of the ridges on the fixed jaw also being of an equal width so that the top angles of the I ridges are smaller at the middle of the working surface and larger nearer to the edges of the same and to the side members.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.

POUL BEOI-IGAARD.

Witnesses H. G. BRANZELL, G. PETERSSON, 

